It may well be because of the recent memory shortage that crucial have had to outsource there memory.However there first class support and warranty should mean that any problems you have with there supplied memory will be quickly resolved regardless of manufacture.
Mikè I can understand your concern, all I am saying is crucial are not going to supply you with substandard products and judging by previous postings about them you are certainly not going to be left high and dry if you have any problems. I would imagine Sony source components for there products from many different sources and although the finished products may appear identical and function to the same high standard the parts may be from different manufacturers.
Possibly Crucial outsource their products from well known manufacturers.Manufacture of memory chips, seems to stem from an handfull of companies, who produce for the vast majority of the market. ie Re-badging.